Keywords: piezoelectric; shoes; piezoelectricshoes
|A passively tunable mechanism for a dual bimorph energy harvester with variable tip stiffness and axial load|
This paper presents a novel vibration-based piezoelectric energy harvester capable of passively tuning its resonant frequency to a wide range of frequencies. The device comprises a dual bimorph with a mass at its free end. A novel sliding mechanism, consisting of two oblique springs connected to the tip mass, is proposed to widen the resonance frequency of the device even to very low frequencies. The application of two oblique springs results in an additional stiffness and axial load that are in...
Keywords: Vibration; Piezoelectric; Energy Harvesting
|Considerations in computing the useful frequency range of piezoelectric accelerometers (Volume NBS Technical Note 487) - Newman, Nathan|
The paper analyzes two lumped-parameter models for computing the usable frequency range of piezoelectric accelerometers.The analyses indicate why application of an electrical excitation to the piezoelectric element of a mounted pickup does not, in general
Keywords: Piezoelectric devices; Accelerometers
|Energy Harvesting Simulation of Piezoelectric ZnO for Electromechanical Nanogenerators|
The study investigates the piezoelectric harvesting efficiency of ZnO microstructures with various structural configurations for electromechanical nanogeneratorsusing finite element method simulation. The effects of ZnO structural parameters for a given cross-section area are simulated, including length, height, array number and shape. In addition, the harmonic responses and model frequencies are evaluated to analyze the natural mode shapes and force vibrations. The r...
Keywords: Piezoelectric; Harvesting; ZnO; Simulation; Electromechanical
|Apparatus for the detection of piezoelectric coupling (Volume 67C) - Frenkel, Lothar|
Journal of Research of the National Bureau of Standards
Keywords: piezoelectric coupling; detection; Giebe; Scheibe; oscillator
|A theory of ionospheric thermal radiation - Hsieh, H. C|
Theory of ionospheric thermal radiation
Keywords: IMPACT LOADS; MICROMETEOROIDS; PIEZOELECTRIC TRANSDUCERS; FORCE DISTRIBUTION
|diffusion2014-02-03 - Diffusion Science Radio|
Phishing and mozzie bite zappers Sperm can smell by Ian Woolf, Mosquito bite zapping by Ian Woolf, Phishing tales by Ian Woolf, presented and produced by Ian Woolf
Keywords: science; Diffusion; mosquito; zanzaclick; piezoelectric; phishing; scam
|Dos Time Live - 34 - Messing with your April, Fools! - DosTimeLive Studios|
Sam does a round up of April Fools Day pranks played by Blizzard and ThinkGeek. In Tech Insight this week, we explore the wonders of new piezoelectric technology, including braille touch-screens and a blood powered iPod! Quinn and Scott share the method needed for us Canadians to get Skype on our iPhones and in photography this week Quinn reviews some great new underwater cameras. All this, a few tips and lots of laughs on this week's Dos Time Live!
Keywords: Apple; April Fools; Canada; iPhone; piezoelectric; podcast; Skype; underwater camera
|User manual for ATILA, a finite-element code for modeling piezoelectric transducers - Decarpigny, J. N. (Jean-Noel), 1958-;Debus, Jean-Claude.|
Title from cover
Keywords: FINITE ELEMENT ANALYSIS; NUMERICAL ANALYSIS; PIEZOELECTRIC TRANSDUCERS; SONAR
|Vibration Based Crack Detection in a Rotating Disk - Gyekenyesi, Andrew L.|
This paper describes the analytical results concerning the detection of a crack in a rotating disk. The concept of the approach is based on the fact that the development of a disk crack results in a distorted strain field within the component. As a result, a minute deformation in the disk's geometry as well as a change in the system s center of mass occurs. Finite element analyses were conducted concerning a notched disk in order to define the sensitivity of the method...
Keywords: PIEZOELECTRIC ACTUATORS; FIBER COMPOSITES; FABRICATION; PATENTS; FILMS; ELECTRIC CONDUCTORS; ELECTRODES
|Application of air bearings to an electrodynamic vibration standard (Volume 67C) - Dimoff, T.|
Journal of Research of the National Bureau of Standards
Keywords: air bearing; electrodynamic vibration standard; piezoelectric accelerometer; calibration
|BSTJ 14: 1. January 1935: Abstracts of Articles from Bell System Sources.|
Bell System Technical Journal, 14: 1. January 1935 pp 173-175. Abstracts of Articles from Bell System Sources.
Keywords: overtone; piezoelectric; harmonic; slit; frequency; pitch; transmission; frequencies; comparison; reeds
|BSTJ 40: 5. September 1961: The Effect of Driving Electrode Shape on the Electrical Properties of Piezoelectric Crystals. (Lewis, J.A.)|
Bell System Technical Journal, 40: 5. September 1961 pp 1259-1280. The Effect of Driving Electrode Shape on the Electrical Properties of Piezoelectric Crystals. (Lewis, J.A.)
Keywords: piezoelectric; capacitance; electrode; crystal; ratio; frequency; admittance; electrical; displacement; crystals; electric displacement; static capacitance; capacitance ratio; bell system; piezoelectric crystals; electrode shape; piezoelectric coupling; electrical properties; system technical; small piezoelectric
|Beyond the Baseline: Proceedings of the Space Station Freedom Evolution Symposium - NON|
This report contains the individual presentations delivered at the Space Station Evolution Symposium in League City, Texas on February 6, 7, 8, 1990. Personnel responsible for Advanced Systems Studies and Advanced Development within the Space Station Freedom Program reported on the results of their work to date. Systems Studies presentations focused on identifying the baseline design provisions (hooks and scars) necessary to enable evolution of the facility to support changing space policy and a...
Keywords: PIEZOELECTRIC ACTUATORS; FABRICATION; ELECTROMECHANICS; AIRCRAFT STRUCTURES; FIBER COMPOSITES; VIBRATION; SHAPES
|Microwave Ultrasonics in Solid State Physics - J. W. Tucker & V. W. Rampton|
J. W. Tucker & V. W. Rampton Microwave Ultrasonics in Solid State Physics North-Holland Publishing Company 1972 Acrobat 7 Pdf 18.4 Mb. Scanned by artmisa using Canon DR2580C + flatbed option
Keywords: Electronics; Physics; Piezoelectric; Dielectric; Ferromagnetic; Paramagnetic; Semiconductor; Semiconductors; Metals; Light
|Active Vibration Control of Piezoelectric Stewart Platform Based on Fuzzy Control|
This paper presents a simulation study aimed at investigating the potential of using fuzzy controller for active vibration control in a piezoelectric Stewart platform. The focus of the study is to assess, through simulation, the control authority of the piezo stack actuators for effectively controlling the Stewart platform vibration. Dynamic analysis of the structure is performed using Matlab/Simulink...
Keywords: Active Vibration Control; Fuzzy Controller; Piezoelectric Stewart Platform
|BSTJ 14: 4. October 1935: Technical Digests: An Electromechanical Representation of a Piezoelectric Crystal Used As A Transducer. (Mason, W.P.)|
Bell System Technical Journal, 14: 4. October 1935 pp 718-723. Technical Digests: An Electromechanical Representation of a Piezoelectric Crystal Used As A Transducer. (Mason, W.P.)
Keywords: crystal; mechanical; electrical; representation; applied; constants; vibrating; piezoelectric; decrement; circuit; crystal vibrating; quartz crystal; electromechanical representation; piezoelectric crystal
|The Topography (and Ephemeris) of Phobos from MOLA Ranging - Banerdt, W. B.|
The MGS spacecraft experienced four close encounters with Phobos in the late summer of 1998. The last (and closest) of these, on September 12, 1998, had an encounter distance of 265 km, well within the maximum MOLA range of 780 km. The apparent motion of Phobos at encounter was 0.7 deg/sec (well in excess of the maximum MGS roll rate of 0.37 sec), which would have resulted in about 6 seconds on target for a fixed spacecraft orientation, or about 10 seconds using a spacecraft roll to partially co...
Keywords: ACTUATORS; PIEZOELECTRIC CRYSTALS; PIEZOELECTRIC CERAMICS; STRUCTURAL DESIGN; VIBRATION ISOLATORS; SMART MATERIALS; PIEZORESISTIVE TRANSDUCERS; STRUCTURAL ENGINEERING; LEAD ZIRCONATE TITANATES; PIEZOELECTRICITY
|mit :: ai :: aim :: AIM-1269|
From the bitsavers.org collection, a scanned-in computer-related document.mit :: ai :: aim :: AIM-1269
Keywords: motors; piezoelectric; pzt; stator; micromotors; ultrasonic; silicon; electrostatic; traveling; rotor; traveling wave; piezoelectric ultrasonic; thin film; energy density; variable capacitance; ultrasonic motors; bottom electrode; glass lens; piezoelectric motors; electrostatic micromotors
|BSTJ 18: 3. July 1939: Abstracts of Technical Articles from Bell System Sources .|
Bell System Technical Journal, 18: 3. July 1939 pp 538-543. Abstracts of Technical Articles from Bell System Sources .
Keywords: telephone; coatings; piezoelectric; radio; stearate; frequencies; harbor; stearic; barium; films; piezoelectric constants; light rubbing; radio telephone; bell system; barium stearate; stearic acid; rubbed films; technical articles
|BSTJ 58: 2. February 1979: Papers by Bell Laboratories Authors.|
Bell System Technical Journal, 58: 2. February 1979 pp 545-547. Papers by Bell Laboratories Authors.
Keywords: amorphous; electron; metallic; polymer; phenomena; singlet; transition; piezoelectric; microstructure; chemisorbed; specific heat
|BSTJ 19: 2. April 1940: Contributors to this Issue.|
Bell System Technical Journal, 19: 2. April 1940 pp 338-339. Contributors to this Issue.
Keywords: telephone; bell; engaged; columbia; telegraph; massachusetts; piezoelectric; university; contributors; electrical; bell telephone; western electric
|A summary of pyrotechnic shock in the aerospace industry - Rader, W. P.|
Pyrotechnic shock data obtained from a survey of the aerospace industry and government agencies are presented. Over 2800 measurements from 30 contributors have been compiled and categorized according to type of pyrotechnic device and structure. A reference document to establish guidelines for designing and testing the pyrotechnic shock environment is provided.
Keywords: ELECTRODES; POSITION (LOCATION); SPARK CHAMBERS; ULTRASONIC RADIATION; MAGNETOSTRICTION; PIEZOELECTRIC TRANSDUCERS; SPARKS
|Full-Scale Wind-Tunnel Studies of F/A-18 Tail Buffet - Meyn, Larry A.|
Tail buffet studies were conducted on a full-scale, production F/A-18 fighter aircraft in the 80 by 120 ft Wind Tunnel at NASA Ames Research Center. The F/A-18 was tested over an angle-of-attack range of 18-50 deg, and at wind speeds of up to 168 ft/s, corresponding to a Reynolds number of 12.3x10(exp 6) based on mean aerodynamic chord and a Mach number of 0.15. The port, vertical tail fin was instrumented and the aircraft was equipped with a removable leading-edge extension (LEX) fence...
Keywords: PIEZOELECTRIC ACTUATORS; MATHEMATICAL MODELS; FINITE ELEMENT METHOD; ELECTRIC POTENTIAL; PIEZOELECTRICITY; FREQUENCY RESPONSE; DEFLECTION; BONDING
|Structural Health Monitoring of Aircraft Wing Using Wireless Network - Nisha. M. S.|
The usage of composites in aircraft industry has enormously increased over the past few decades and has led to the development of modern trends. This improves the cutting edge technology which provides an outsourcing service from designing to manufacturing. This study is concerned with the detection and characterization of hidden defects in composite structures before they grow to a critical size. Its immediate application is in the health monitoring of aircraft structure in order to detect crac...
Keywords: Composites; Structural Health Monitoring System; Lamb wave; Frequency Response Techniques; piezoelectric actuators
|Aerothermal Analysis of the X-34 Vehicle - Green, Mike|
The X-34 vehicle will provide the first flight demonstration under NASA's Reusable Launch Vehicle (RLV) program of a fully reusable launch vehicle. Under a fixed-price contract with NASA, Orbital Sciences Corporation (OSC) i s to provide a Mach 8 suborbital RLV technology demonstrator. The vehicle i s 18.3 meters in length, has a wingspan of 8.4 meters, and is powered by a single LOX-kerosene engine...
Keywords: DESIGN ANALYSIS; FLUID DYNAMICS; DYNAMIC STRUCTURAL ANALYSIS; PIEZOELECTRIC ACTUATORS; PIEZOELECTRICITY; MODELS; FLAPPING; DYNAMIC RESPONSE; DYNAMIC MODELS
|Explore Full Range of QSO/AGN Properties - Wilkes, Belind|
The goal of the proposal is to perform ISO spectroscopic studies, including data analysis and modeling, of star formation regions using an ensemble of archival space-based data from the Infrared Space Observatory s Long Wavelength Spectrometer and Short Wavelength Spectrometer, but including as well some other spectroscopic databases. Four kinds of regions are considered in the studies: (1) disks around more evolved objects; (2) young, low or high mass pre-main sequence stars in star formation r...
Keywords: GENETIC ALGORITHMS; PIPES (TUBES); ROBOTS; PIEZOELECTRIC ACTUATORS; ROBOTICS; INSPECTION; ENERGY CONSUMPTION; SIMULATION
|Space Station Science Payload Integration Management Study - NON|
The Space Station Science Payload Integration Management Study was performed to provide the Office of Space Science and Applications (OSSA) with a concept and recommendation for managing the major integration activities for OSSA Science payloads during the Space Station era beginning with Permanent Manage Capability (PMC) through mature operations. It is anticipated that OSSA will manage and provide the majority of the United States user Science Payloads that are conducted on the Space Station...
Keywords: DAMPING; STIFFNESS; FEEDBACK CONTROL; MATHEMATICAL MODELS; PIEZOELECTRIC CERAMICS; SMART STRUCTURES; TRUSSES; ACTUATORS; COMPOSITE MATERIALS; FLEXIBLE BODIES
|Effect of Piezoelectric Layer on Beam Parameters using Zigzag Theory|
An efficient higher order theory is presented forstatic analysis of multilayered composite beams withpiezoelectric layers embedded or bonded to the surface, understatic electromechanical load. In this theory, the in-planedisplacement field is taken as a combination of a layer-wiselinear variation and a cubic variation across the thickness.Transverse normal strains are neglected. The electric field isalso approximated as piecewise linear across the sub layers.The displacement field is expressed i...
Keywords: zigzag theory; hybrid beam; piezoelectric layer; static analysis; thickness; electromechanical loading
|Decomposition-Based Decision Making for Aerospace Vehicle Design - Borer, Nicholas K.|
Most practical engineering systems design problems have multiple and conflicting objectives. Furthermore, the satisfactory attainment level for each objective ( requirement ) is likely uncertain early in the design process. Systems with long design cycle times will exhibit more of this uncertainty throughout the design process. This is further complicated if the system is expected to perform for a relatively long period of time, as now it will need to grow as new requirements are identified and ...
Keywords: PIEZOELECTRIC GAGES; STRUCTURAL ANALYSIS; CRYOGENIC EQUIPMENT; SYSTEMS HEALTH MONITORING; IMPEDANCE; LOW TEMPERATURE TESTS
|Space programs summary no. 37-62, volume 2 for the period 1 January - 28 February 1970. The Deep Space Network - NON|
Deep Space Network operations review
Keywords: PIEZOELECTRIC CRYSTALS; SEMICONDUCTORS (MATERIALS); WAVE PROPAGATION; ELASTIC WAVES; EQUATIONS OF MOTION; MAXWELL EQUATION; PROPAGATION VELOCITY
|Solid State Physical Electronics - Aldert van der Ziel|
Aldert van der Ziel Solid State Physical Electronics 2nd.ed. (Prentice-Hall Electrical Engineering Series) Prentice-Hall Inc. 1968 Acrobat 7 Pdf 25.8 Mb. Scanned by artmisa using Canon DR2580C + flatbed option
Keywords: Electronics; Wave Mechanics; Band Theory; Diodes; Transistors; Emission; Piezoelectric; Ferroelectric; Laser; Maser; Magnetism
|A Study of Technical Engineering Peer Reviews at NASA - Chao, Lawrence P.|
This report describes the state of practices of design reviews at NASA and research into what can be done to improve peer review practices. There are many types of reviews at NASA: required and not, formalized and informal, programmatic and technical. Standing project formal reviews such as the Preliminary Design Review and Critical Design Review are a required part of every project and mission development...
Keywords: FABRICATION; PERFORMANCE TESTS; GIMBALS; PIEZOELECTRIC CERAMICS; THERMAL EXPANSION; THERMOPLASTICITY; METAL FOILS; HIGH TEMPERATURE
|The self-modeling problem of a high-current discharge in a plasma - Volosevich, P. P., et al|
Self-modeling solutions of high-current plasma discharge and effect of thermal conductivity
Keywords: ELECTRIC PULSES; HIGH PRESSURE; HIGH TEMPERATURE TESTS; PULSE DURATION; ROCKS; ELASTIC WAVES; PIEZOELECTRIC TRANSDUCERS; THERMAL STABILITY
|BSTJ 30: 4. October 1951: Frequency Dependence of Elastic Constants and Losses in Nickel. (Bozorth, R.M.; Mason, W.P.; McSkimin, H.J.)|
Bell System Technical Journal, 30: 4. October 1951 pp 970-989. Frequency Dependence of Elastic Constants and Losses in Nickel. (Bozorth, R.M.; Mason, W.P.; McSkimin, H.J.)
Keywords: domain; crystals; rod; nickel; equation; piezoelectric; williams; domains; impedance; sinh; domain size
|BBC Research and Development Report Number 1981-12|
R&D Report 1981-12 : Piezoelectric plastic transducers -- a feasibility study. M.A. Parker The properties of certain piezoelectric plastics are outlined and these are used to postulate transducer designs. The characteristics of two types of dome radiator which were made from these materials are discussed in detail. Whilst these transducers were able to produce subjectively reasonable sound levels when incorporated in a loudspeaker system, they proved to be considerably less sensitive than their ...
Keywords: dome; piezoelectric; khz; fluoride; plastic; tweeter; frequency; polyvinylidene; material; transducers; vacuum forming; plastic transducers; polyvinylidene fluoride; measuring point; frequency response; dome units; electric field; polyvinyl chloride; piezoelectric plastic; feasibility study
|BSTJ 46: 8. October 1967: Equations Governing the Electrical Behavior of an Arbitrary Piezoelectric Resonator Having N Electrodes. (Lloyd, P.)|
Bell System Technical Journal, 46: 8. October 1967 pp 1881-1900. Equations Governing the Electrical Behavior of an Arbitrary Piezoelectric Resonator Having N Electrodes. (Lloyd, P.)
Keywords: resonator; admittance; piezoelectric; impedance; behavior; equations; electrodes; electrical; matrix; terminals; open circuit; normal modes; piezoelectric resonator; boundary conditions; electrical behavior; reciprocal theorem; external electrical; bell system; system technical; impedance matrix
|BSTJ 37: 3. May 1958: Piezoelectric and Dielectric Characteristics of Single-Crystal Barium Titanate Plates. (Meitzler, A.H.; Stadler, H.L.)|
Bell System Technical Journal, 37: 3. May 1958 pp 719-738. Piezoelectric and Dielectric Characteristics of Single-Crystal Barium Titanate Plates. (Meitzler, A.H.; Stadler, H.L.)
Keywords: crystal; polarization; dielectric; admittance; average; resonant; crystals; piezoelectric; frequency; constant; piezoelectric output; output voltage; dielectric constant; single crystal; average polarization; bell system; titanate plates; single crystals; system technical; batioa single
|BSTJ 26: 1. January 1947: First and Second Order Equations for Piezoelectric Crystals Expressed in Tensor Form. (Mason, W.P.)|
Bell System Technical Journal, 26: 1. January 1947 pp 80-138. First and Second Order Equations for Piezoelectric Crystals Expressed in Tensor Form. (Mason, W.P.)
Keywords: tensor; constants; piezoelectric; elastic; equation; dxi; crystal; equations; constant; crystals; second order; second rank; tensor form; system technical; elastic constants; spontaneous polarization; technical journal; piezoelectric crystals; bell system; rochelle salt
|mit :: ai :: aim :: AITR-1634|
From the bitsavers.org collection, a scanned-in computer-related document.mit :: ai :: aim :: AITR-1634
Keywords: stator; rotor; figure; motors; piezoelectric; stall; ultrasonic; torque; motor; pzt; pressure distribution; piezoelectric ultrasonic; stall torque; output power; normal force; stall torques; ultrasonic motor; traveling wave; ultrasonic motors; energy density
|Status of Duct Liner Technology for Application to Aircraft Engine Nacelles - Parrott, Tony L.|
Grazing flows and high acoustic intensities impose unusual design requirements on acoustic liner treatments used in aircraft engine nacelles. Increased sound absorption efficiency (requiring increased accuracy of liner impedance specification) is particularly critical in the face of ever decreasing nacelle wall area available for liner treatments in modern, high-bypass ratio engines. This paper reviews the strategy developed at Langley Research Center for achieving a robust measurement technolog...
Keywords: BUFFETING; FLIGHT TESTS; ANGLE OF ATTACK; ACTIVE CONTROL; ACTUATORS; STABILIZERS (FLUID DYNAMICS); PIEZOELECTRIC ACTUATORS; STRUCTURAL STABILITY; TAIL ASSEMBLIES; FATIGUE (MATERIALS)
|BSTJ 25: 3. July 1946: Abstracts of Technical Articles by Bell System Authors.|
Bell System Technical Journal, 25: 3. July 1946 pp 532-536. Abstracts of Technical Articles by Bell System Authors.
Keywords: amplitude; radar; piezoelectric; relative; dielectric; attenuation; fungi; transmission; properties; insulation; insulation resistance; cent relative; bell system; technical articles
|Biological-Physical Coupling in the Gulf of Maine: Satellite and Model Studies of Phytoplankton Variability - Thomas, Andrew C.|
The goals of this project were to acquire, process, QC, archive and analyze SeaWiFS chlorophyll fields over the Gulf of Maine and Scotia Shelf region. The focus of the analysis effort was to calculate and quantify seasonality and interannual. variability of SeaWiFS-measured phytoplankton biomass in the study area and compare these to physical forcing and hydrography. An additional focus within this effort was on regional differences within the heterogeneous biophysical regions of the Gulf of Mai...
Keywords: ACTUATORS; SHORT CIRCUITS; LEAD ZIRCONATE TITANATES; PIEZOELECTRIC CERAMICS; FIBER COMPOSITES; FABRICATION; ELECTRIC POTENTIAL; LOW COST; STRAIN GAGES; CAPACITANCE; ELECTRIC DIPOLES
|Pressure measurements in basalt Final report, 13 Jun. 1966 - 13 Feb. 1967 - NON|
Pressure-time profile measurements on projectile hypervelocity impact by manganin wire pressure transducer
Keywords: HYPERVELOCITY IMPACT; PIEZOELECTRIC GAGES; PRESSURE MEASUREMENT; PRESSURE SENSORS; ELECTRIC WIRE; HYPERVELOCITY PROJECTILES; MANGANESE ALLOYS; MANGANIN (TRADEMARK); REACTION TIME
|THE DC GENERATORS FOR UTILIZING WIND POWER - CARRER, A|
THEORETICAL CONSIDERATIONS ARE EXPLAINED AND EXPERIMENTAL FINDINGS PERTAINING TO THE POSSIBILITY OF UTILIZING WIND POWER WITH ELECTROMECHANICAL UNITS COMPRISING VARIOUS TYPES OF DIRECT CURRENT MACHINES.
Keywords: FLAT PLATES; PIEZOELECTRIC TRANSDUCERS; PRESSURE OSCILLATIONS; TURBULENT BOUNDARY LAYER; FLAT SURFACES; HYPERSONIC FLOW; PRESSURE DISTRIBUTION; SHEAR STRESS; WALL FLOW
|Laboratory studies of interplanetary dust - Walker, R. M|
Interplanetary dust particles (IDPs) are a form of primitive extraterrestrial material. In spite of the formidable experimental problems in working with particles that are too small to be seen with the naked eye, it has proven possible to obtain considerable information concerning their properties and possible origins. Dust particles collected in the stratosphere were reviewed. These particles are the best available samples of interplanetary dust and were studied using a variety of analytical te...
Keywords: ACOUSTIC EMISSION; DAMAGE; FATIGUE (MATERIALS); METAL POWDER; MICROSTRUCTURE; MORPHOLOGY; PIEZOELECTRIC TRANSDUCERS; SIGNAL PROCESSING; WAVE ATTENUATION; COMPOSITE MATERIALS; CONFERENCES; NONDESTRUCTIVE TESTS; ULTRASONIC RADIATION; ULTRASONICS; WAVE PROPAGATION; CHARACTERIZATION; CRACK PROPAGATION
|Exploring Martian Impact Craters: Why They are Important for the Search for Life - Schwenzer, S. P.|
Fluvial features and evidence for aqueous alteration indicate that Mars was wet, at least partially and/or periodically, in the Noachian. Also, impact cratering appears to have been the dominant geological process  during that epoch. Thus, investigation of Noachian craters will further our understanding of this geologic process, its effects on the water-bearing Martian crust, and any life that may have been present at the time...
Keywords: AEROSPACE VEHICLES; ARCHITECTURE (COMPUTERS); EMBEDDED COMPUTER SYSTEMS; DATA ACQUISITION; PANELS; COMPUTERIZED SIMULATION; ALGORITHMS; ALUMINUM; ROBOTICS; SYSTEMS HEALTH MONITORING; NONDESTRUCTIVE TESTS; SENSORS; AVIONICS; PIEZOELECTRIC TRANSDUCERS; INSPECTION; COMPUTER PROGRAMS
|Realistic Subscale Evaluations of the Mechanical Properties of Advanced Disk Superalloys - Gabb, Timothy P.|
A series of experimental powder metallurgy disk alloys were evaluated for their processing characteristics and high temperature mechanical properties. Powder of each alloy was hot compacted, extruded, and isothermally forged into subscale disks. Disks were subsolvus and supersolvus heat treated, then quenched using procedures designed to reproduce the cooling paths expected in large-scale disks. Mechanical tests were then performed at 538, 704, and 815 C...
Keywords: MOIRE INTERFEROMETRY; AERODYNAMIC NOISE; OPTICAL MEASUREMENT; ROTOR AERODYNAMICS; ROTARY WING AIRCRAFT; DEFORMATION; ROTORS; WIND TUNNEL TESTS; PIEZOELECTRIC ACTUATORS; FIBER COMPOSITES; LOADS (FORCES)
|Noise, Turbulence, and Thrust of Subsonic Free Jets from Lobed Nozzles - Zaman, K. B. M. Q.|
A study of noise benefit, vis-a-vis thrust penalty, and its correlation to turbulence intensities was conducted for free jets issuing from lobed nozzles. Four convergent nozzles with constant exit area were used in the experiments. Three of these were of rectangular lobed configuration having six, ten and fourteen lobes; the fourth was a circular nozzle. Increasing the number of lobes resulted in a progressive reduction in the turbulence intensities as well as in the overall radiated noise...
Keywords: FLOW VISUALIZATION; PARTICLE IMAGE VELOCIMETRY; PIEZOELECTRICITY; PRESSURE GRADIENTS; SECONDARY FLOW; VORTEX GENERATORS; FLOW MEASUREMENT; CONTROL EQUIPMENT; PIEZOELECTRIC ACTUATORS; VORTICES; ACTUATORS; BOUNDARY LAYERS; INTERNAL FLOW; LOW SPEED
|An Engineering Aerodynamic Heating Method for Hypersonic Flow - Riley, Christopher J.|
A capability to calculate surface heating rates has been incorporated in an approximate three-dimensional inviscid technique. Surface streamlines are calculated from the inviscid solution, and the axisymmetric analog is then used along with a set of approximate convective-heating equations to compute the surface heat transfer. The method is applied to blunted axisymmetric and three-dimensional ellipsoidal cones at angle of attack for the laminar flow of a perfect gas...
Keywords: NAVIER-STOKES EQUATION; TIME DEPENDENCE; PIEZOELECTRIC ACTUATORS; AMBIENT TEMPERATURE; DISCRETIZATION (MATHEMATICS); REYNOLDS AVERAGING; UNSTEADY FLOW; COMPUTERIZED SIMULATION; COMPUTATIONAL FLUID DYNAMICS; FLOW REGULATORS; JET FLOW; AIR FLOW; ALGORITHMS